Sound-box mounting for talking-machines



J. C. DRAKE.

SOUND BOX MOUNTING FOR TALKING MACHINES.

APPLICATION FILED FEB-19, 1920.

Patented July 19, 1921.

attouwq UNITED, STATES PATENT OFFICE.

JAMES C. DRAKE, OF ROCHESTER, MINNESOTA, ASSIGNOR T0 SEARS, ROEBUCK AND SOUND-BOX MOUNTING FOR TALKING-MACHINES.

T 0 all whom it may concern:

Be it known that I, JAMES C. DRAKE, a citizen of the United States, residing at Rochester, in the county of Olmsted, State of Minnesota, have invented certain new and useful Improvements in Sound-Box Mountings for Talking-Machines, of which the following is a specification, reference being had therein to the accompanying drawin y invention relates to sound recor ing and reproducing machines and especially sound box mountings therefor.

An object of my invention is to provide a simple and e ective arrangement for mounting a sound box upon the tone arm of a machine of the above ty e.

I attain my object in the ollowing manner: I provide the tone arm with a short terminal tube, which is pivoted to the arm to have lay upward and downward with respect thereto. This tube receives either one of two short adapters or attachments, to which the sound box is attached.

One end of each adapter is provided with a neck, and a guide working in a slot, in the collar attached to the sound box. The other end of each adapter has a radially projecting screw attached to it, and upon the screw a nut with knurled edge to be turned by the fingers without a tool, the inner face of the nut being concave. This end of the adapter fits in the end of the terminal tube on the tone arm, which said tube is provided with a single slot to receive the screw on the adapter, and on both sides ofthe slot a convex projection fitting the inner concave face of the nut, so that the nut when screwed down clamps the adapter on the tube end, while the slot serves as a guide and determines the correct angular position of the adapter on the tube.

This application is a division of my coendin application filed April 17, 1917,

erial filo. 162,7 47

My invention is illustrated in theaccompanying drawings in which igure 1 is a top plan view of a portion of a tone arm with one form of sound box connecting elbow or adapter attached and with the sound box removed;

Fig. 2 is a side elevat'on of the same with sound box attached;

Fig. 3 is a fragmentary side view of the Specification of Letters Patent.

Patented July 19, 1921.

Serial No. 162,747. Divided and this application filed February jointed end of the tone arm showing the guide slot and convex projections;

Fig. 4 is a top plan view of the elbow adapter shown in Fig. lbut removed from the tone arm;

F 1g. 5 is a side View of the adapter of Fig. 4c;

.F1g. 6 is a side view of the sound box mounting assembled with the adapter for playing vertically cut records, its screw belng at right angles to that of Figs. 1 and 4, with respect to the sound box.

Fig. 7 is a section on the line m-w of F lg. l.

'teferring to the details of the drawings, 1 indicates the body of the tone arm. The hollow tone arm 4; communicates with a suitable horn or amplifier not shown. The tone arm is provided at its free end with a short pivoted tubularsection 5 forming the terminal of the tone arm proper. This tone arm terminal 5 is provided with a laterally projecting double convexity or stud 6 and is split or slotted at 7 the slot passing between the two convexities 6. By the provision of the slot 7 a certain amount of expansion of the circumference of the end of the section 5 is afforded, and to increase the expansibility of the tube at this locality, I reduce the thickness of the wall of the tube as indicated at 8 from the free end inward to a depth slightly greater than that of the slot 7, as indicated by the dotted line 9. Preferably the convexities6 are embossed in the tube 5, although it may of course be cast orbsoldered or otherwise formed upon the tu e.

For the purpose of connecting the sound box to this tone arm terminal 5, I provide a pair of interchangeable elbow adapters 10 and 11, shown also in Figs. 4;, 5 and 6, which elbows vary somewhat in length and angular adjustment. This variation, as stated, is for the purpose of connecting the same sound box, or sound boxes of the same type,.with the tone arm in difi'erent angular relations thereto according to the type of record to be played. For example, the adapter 10 is for use with records of the laterally undulating groove type, while the adapter 11 (Fig. 6) is for use with records of the perpendicularly-undulating-groove t pe.

In Figs. 1 and 2, I have shown t e adapter 10 in operative connection with the tone arm terminal 5, Fig. 1, without the sound box, and Fig. 2 with the sound box 12. The adapter 10 consists of a tube bent in the form of a rectangular elbow having one end reduced as at 13 to fit within the tone arm terminal 5 and forming a shoulder 14. Mounted on the reduced portion 13 and projecting outwardly and radially therefrom is a screw 15 which is held fixed in the elbow, preferably by a soldered head 16. This screw is of such diameter as'to enable it to pass into the slot when the reduced end 18 of the elbow is passed into the tone arm terminal 5 and is so spaced from the shoulder 14 that upon the engagement of the shoulder with the end of the tone arm terminal, the said shank will be positioned in the slot concentrically with the convexities 6. A lock nut 17 is carried by the screw in threaded engagement therewith and is provided with a concavity 18 on its inner surface for engagement with the convexities 6. (See particularly sectional Fig. 7). The engaging surfaces of the parts 5 and 13 are so proportioned in relation to each other that their engagement causes a slight distortion or expansion of the slotted end of the member 5 so that the resiliency of the reduced portion 8 together with the clamping effect of the lock nut 17 will afford a tight non-vibrating connection, the engagement of the convexities 6 with the socket 18 forming a positive lock. The outer end 19 of the adapter 10 is reduced to form a shoulder 20, the reduced portion having a longitudinal slot 21 therein which acts as a guide for positioning the sound box. The arrangement of the sound box terminal for engagement with this.

outer end 19 of the elbow is shown in Fig. 7 and consists of the tubular extension 22 fittedwith a bushing 23 of rubber or other suitable elastic sound insulating material. The inside diameter of the elastic bushing 23 is slightly less than the outside diameter of the reduced end 19 of the adapter 10 so as to fit thereover with a slight compression of the bushing. A guiding stud or shank 2 1 is carried by the tubular extension 23 and extends inwardly and radially thereoi'. through the bushing a suflicient distance to engage with the slot 21 in the end of the elbow. This guide shank 241- is so positioned that when the sound box is coupled onto the elbow, the axis of the stylus point 25 will take the angular position indicated in Fig. 2. Thus, as shown in Fig. 2, when the sound box is connected with the tone arm by the adapter 10, the parts are. in. the correct relative adjustment for playing records of the laterally-undulatinggroove type.

The adapter 11 has its coupling ends 26 and 27 formed identically like the corresponding ends 13 and 19 of the adapter 10, the end 26 being reduced and provided with a screw 28 and socketed lock nut 29 arranged to cooperate with the tone arm terminal 5, and the end 27 reduced and pro vided with a slot 30 for cooperation with the coupling means carried by the sound. box 12, so that the ends 27 and 28 may cooperate with the tone arm terminalv and the sound box terminal interchangeably with the corresponding portions of the adapter 10.

Having thus described my invention what I claim and desire to secure by Letters Patent is:

A coupling for sound boxes of talking machines comprising a slotted tubular female member carrying a convex stud on each 1 side of the slot, a male member carrying a radial screw passing into said slot and lying in the axis of said stud, and a traveling nut on said screw with a concave inner face to engage both sides of the stud when the nut is screwed home to wedge them together so as to tighten the grip of the female member on the male member, and at the same time to lock the parts against any endwise movement with respect to the slot.

In testimony whereof I ailix my signature.

JAMES C. DRAKE.

Witnesses J. EADMAN, FRED L. WILLIAMS. 

